Table 2.

Prevalence and cumulative incidence of autism spectrum disorders for each study year and for the total study years

		Year 2013	2014	2015	2016	Total
Ascertained cases	male	14	13	18	15	60
	female	8	7	7	5	27
	total	22	20	25	20	87
N of children with ASD born in the catchment area	male	8	9	14	13	44
	female	5	7	6	5	23
	total	13	16	20	18	67
A total N of 5-year-old children in the catchment area	male	685	639	600	625	2549
	female	625	622	621	599	2467
	total	1310	1261	1221	1224	5016
N of 5-year-old whose caregivers returned the screening questionnaire	male	506	496	489	531	2022
	female	449	468	515	500	1932
	total	954	964	1004	1031	3954
N of the birth cohort in the catchment area	male	703	648	639	603	2593
	female	656	610	664	589	2519
	total	1359	1258	1303	1192	5112
Crude orevalence (%) (95% confidence interval: CI)	male	2.04 (0.98–3.10)	2.03 (0.94–3.13)	3.00 (1.64–4.36)	2.82 (1.42–4.23)	2.35 (1.76–2.94)
	female	1.28 (0.40–2.16)	1.13 (0.30–1.95)	1.13 (0.30–1.96)	0.83 (0.11–1.56)	1.09 (0.68–1.51)
	total	1.68 (0.98–2.38)	1.59 (0.90–2.28)	2.05 (1.25–2.84)	1.63 (0.92–2.34)	1.73 (1.37–2.10)
Adjusted prevalence (%) (95% CI)	male	–	–	–	–	4.06 (3.20–4.92)
	female	–	–	–	–	2.22 (1.57–2.88)
	total	–	–	–	–	3.22 (2.66–3.76)
Cumulative incidence up to 5 years of age (%) (95% CI)	male	1.14 (0.35–1.92)	1.39 (0.49–2.29)	2.19 (1.06–3.33)	2.16 (1.00–3.32)	1.70 (1.20–2.19)
	female	0.76 (0.10–1.43)	1.15 (0.30–1.99)	0.90 (0.18–1.62)	0.85 (0.11–1.59)	0.91 (0.54–1.28)
	total	0.96 (0.44–1.47)	1.27 (0.65–1.89)	1.53 (0.87–2.20)	1.51 (0.82–2.20)	1.31 (1.00–1.62)

ASD autism spectrum disorder, Prevalence (%) N of ASD cases/the total N of target population in the catchment area × 100

Five-year cumulative incidence (%) N of ASD cases who were born in the catchment area/N of the birth cohort in the catchment area × 100